Identify this pack?

[Bhoesl]

I found this used Mystery Ranch pack listed for sale really cheap, the guy says he doesn't know anything about it, model, size, etc, but that its in great shape. Anyone know what pack this is? Doesn't seem to match anything I can find online...
Thanks

 

[ZBB]

Big Sky is the model?/pack. I googled “MR big sky pack” and got a bunch of different results to look through.